1. Field of the Invention
The heights of most tabletops, desktops, and chair seats and arms as well as chair widths have become somewhat standardized in the Western world in ergonomic response to the dimensions of the average contemporary adult human frame. Tabletop and desktop surfaces are generally raised between twenty-seven and twenty-nine inches above the floors that their legs or other supports rest upon. Dining chair seating surfaces are generally raised to roughly sixteen inches above the floor, with a slightly greater (typically one-half to one inch) elevation at their front edge above the rear edge next to the back of the chair. This sloping angle provides comfort for those who sit in the chair. The arm heights for these types of chairs are typically made short enough to fit under a tabletop of conventional depth, which depth is typically up to two inches. This dictates a maximum arm height for dining chairs of roughly twenty-five inches. Seating surfaces for lounge chairs are generally lower than those same surfaces for dining chairs, and more sharply sloped downward at their rear edges so as to provide a more reclining posture to those people who use them than do dining chair seats. The rear edge of lounge chair seats may thus be as little as nine to twelve inches above the floor that the chair rests upon.
Given these dimensions, the present invention is directed to the use of rectangular wooden boards, metal bars or rods, or plastic or metal tubes to compose the base structure of a modular, foldable or easily disassembled and reassembled and thus compactly storable and transportable furniture system. The system's interchangeable modules can be used cost-effectively to interchangeably compose a number of furniture applications, such as dining chairs and dining tables, worktables, or desktops, as well as lounge chairs and storage cabinets.
This modular furniture system supports a variety of furniture application modules on a base structure composed from rigid rectilinear materials with members composed of appropriately-sized rectangular cross-sections. This convertible framework can be used to support a single, removable, foldable chair seat and back module in either dining chair or lounge chair applications. Both chair applications provide the user with armrests. Whether the chair is used for a dining or lounge seating application is determined by the base structure's position after the seat-and-back module is removed from the base structure in either chair position and the base structure is then rotated by ninety degrees around one bottom-side axis and the seat-and-back module is re-inserted. Or the structure can be used for supporting a tabletop (or desktop or worktable, if the surface is used as such) after the seat-and-back module is removed and the framework is rotated ninety degrees around a different axis. The base structure in the dining or lounge chair positions can also be used to support a storage cabinet module with drawers or doors. Once erected, the base structure can be adapted to the desired application and support that module for which it is to be used by simply rotating the base structure to the proper erect position and inserting the application module, whether chair seat, table top, or cabinet.
The base structure may be formed from metal bars or wooden boards, or hollow plastic or metal tubes and straps of flexible materials, all configured with a rectangular cross section with dimensions for the members of roughly two-and-a-half to three inches in width, three-quarters of an inch in thickness and between roughly twenty to twenty-five inches in overall length. These dimensions will provide a uniform opening width of roughly eighteen inches for the seat-and-back module when held in both lounge and dining chair positions. These common dimensions permit the use of the same seat and backrest module in both applications.
The framework's bar, board, or tubular members are configured as perpendiculars in a roughly cubical shape, with sides forming two “H” shapes rotated by ninety degrees relative to each other on two opposing faces, two “U” shapes similarly positioned on two other opposing faces, and squares when viewed from the remaining two opposite faces. The removable seat is formed from two pieces of flexible material such as leather or fabric that are sewn or glued together at their rear edge, and that is equipped with corner pins or brackets or other bracing devices which permit the seat to be affixed securely in position on the framework. With the base structure is set in the dining chair position, any weight imposed on the frame will be borne up by three upright “legs,” two at the front and one centered behind the seat. The overall height of the arms of the base in the dining chair position should be no more than approximately twenty-five inches in order to permit the arms of the chair to pass beneath the dining tabletop when it is in place on top of another copy of the base structure. If the rectangular cross-section of the arms of the chair is roughly two-and-a-half to three inches wide by three-quarters to one inch in depth, then the width between the arms of the base structure in the dining chair position and in the lounge chair position will be separated by a close-to-identical width. This will permit the use of the same folding seat module when the chair is configured in either position.
The tabletop can be made collapsible from two pieces of board which are pinned together and held in place by further pins inserted into the base structure. The cabinet module fits into the upper portion of the framework when it is placed in either the dining chair or lounge chair positions but minus the removable seat, and is held in place by an overhanging lip protruding over the side and rear edges of the framework structure and protruding pins that fit into the seat's mounting holes on the framework.
2. Description of the Prior Art
According to Wikipedia, the chair, as composed of a seat and a back supported by four legs, is a device of extreme antiquity that did not pass into popular use until the 16nth Century. The stool, composed only of a seat resting on three or four legs, is believed to be even more ancient. Until the Industrial Revolution, carpenters and other woodworking craftsmen seemed to focus most of their creative efforts on decorative embellishments rather than functional improvements to the design of commonplace furniture objects.
However, by the mid-Nineteenth Century urbanization made it increasingly common for even by persons of means to inhabit relatively compact dwelling spaces. This trend in turn created a growing interest in and demand for furniture that could serve a number of purposes. This was especially true for pieces that could be broken down into components or easily folded to permit them to be compactly stored when not in use.
These forces inspired such innovations as are evident in U.S. Pat. No. 191,733, issued to James P. True on Jan. 5, 1877, for a “Convertible chair,” an upright upholstered arm chair that transforms into what is now called a recliner lounge chair, or in U.S. Pat. No. 321,230 issued on Jun. 30, 1885 to Edward H. Lewis for a somewhat similar “Convertible chair” that also converts from an upright chair to a lounge chair to a bed. By the early Twentieth Century, designs for folding dining-height and lounge chairs both with and without arms were common.
Subsequently patented art that incorporates at least one feature in common with the present invention include:
U.S. Design Pat. No. DI55273, issued on Sep. 20, 1949 to the now-famed furniture designer, Charles Eames, shows a chair with formed metal legs supporting a seat and a backrest, featuring only three legs with one leg in front.
U.S. Pat. No. 2,692,637, issued on Oct. 10, 1954 to Orman N. Rainwater for a “Folding Extensible Height Chair,” shows a folding chair design composed of four “U”-shaped framing support components.
U.S. Pat. No. 2,903,313, issued on Sep. 8, 1959 to Walter W. Block, for a “Portable Folding Table” that features “U”-shaped supporting members.
U.S. Pat. No. 3,640,576 issued on Feb. 8, 1972 to Morrison, et.al, for a “Furniture Construction” consisting of a modular side chair or lounge chair, with or without arms, that features a seat and back composed of a single piece of flexible material suspended above the floor on two two-legged “U”-shaped base structures, either with or without arms, with the base structures held apart by two rigid rollers from which the flexible material is suspended.
U.S. Pat. No. 3,420,571 issued Jan. 7, 1969 to James C. Moore, for a “Collapsible Combination Chair and Desk,” in which the desk is convertibly affixed to the rear of the folding chair.
Interest in modular office furniture systems burgeoned in the post-War period in America, with architects and engineers most often leading the way. As examples, U.S. Pat. No. 3,726,551 was issued on Apr. 10, 1973 to Nat Levenberg for a “Tubular Rigid Angled Joint” for a modular furniture system composed by means of tubular rectangular metal connectors. Somewhat similarly, U.S. Pat. No. 3,767,237, which was issued on Oct. 23, 1973 to Bernard Suchowski, describes a “Miter Frame Corner Construction,” consisting of a device to reinforce the orthogonality of perpendicularly joined members.
U.S. Pat. No. 4,525,009, issued to de la Sota Martinez on Jun. 25, 1985, describes another “Chair changeable into easy chair” design for a tubular-membered, some members being “U”-shaped, upright chair that can be converted into a recliner-lounger by means of a partial rotation around the front edge of the chair.
U.S. Pat. No. 5,085,447, issued Feb. 4, 1992 to Jacques J. Audibert, describes a “Folding furniture structure.” This folding modular concept can take the form of a table, upholstered lounge chairs, or bed, depending on how the components are rotated or collapsed about various axes.
U.S. Pat. No. 5,709,428 issued on Jan. 20, 1998 to Joel F. Hugghins, is for “Collapsible folding furniture.” This design features a roll-up, flexible sling seat and back, and a frame that can be disassembled into a number of fairly short, straight pieces which can be stored together as a single, compact bundle.
U.S. Pat. No. 5,954,391, issued to Donald F. Gray on Sep. 21, 1999, is for a “Stable three legged folding chair.” The chair includes both a seat and a back, but is based on a tripod configuration.
Even without known benefit of patent protections, contemporary furniture designers have continued to publicly explore many variations on what is sometimes called “transformable flat pack” multi-purpose, easily assembled, slotted furniture designs. As of the date of this filing, you may go to http://weburbanist.com/2008/01/13/more-creative-furniture-for-cramped-urban-living-20-pieces-of-ingenious-flat-pack-urban-furniture/ to see illustrations of these kinds of designs. Alternatively, Roel Verhagen Kaptein's 2007 “Transformer Chair” converts from a lounger to chaise lounge to sofa by means of axial rotation of connected components. To see an illustration of this design, use the Internet and go to http://www.yankodesign.com/2008/02/21/transformer-chair-more-than-meets-the-eye/. Two other contemporary designs for chairs that can be converted into chair and desk combinations by means of rotations of up to 180 degrees around their forward axis may be viewed on the Internet at http://dornob.com/flip-over-furniture-convertible-chair-and-desk-design/.